html, body {
    height: 100%;
    width: 100%;
}

body {
    position: relative;
}

.content_body {
    width: 100%;
    height: 100%;
    background: url("") no-repeat;
    background-size: 100% 100%;
    position: relative;
    /*overflow: hidden;*/
    overflow: auto;
    -webkit-overflow-scrolling: touch;
}